On Tue, Jan 17, 2023 at 04:04:22PM -0800, Luis Chamberlain wrote:

./tools/testing/selftests/kmod/kmod.sh -t 0006
Tue Jan 17 23:18:13 UTC 2023
Running test: kmod_test_0006 - run #0
kmod_test_0006: OK! - loading kmod test
kmod_test_0006: FAIL, test expects SUCCESS (0) - got -EINVAL (-22)
----------------------------------------------------
Custom trigger configuration for: test_kmod0
Number of threads:      50
Test_case:      TEST_KMOD_FS_TYPE (2)
driver: test_module
fs:     xfs
----------------------------------------------------
Test completed

When can multiple get_fs_type() calls be issued on a system? When
mounting a large number of filesystems. Sadly though this issue seems
to have gone unnoticed for a while now. Even reverting commit
6e6de3dee51a doesn't fix it, and I've run into issues with trying
to bisect, first due to missing Kees' patch which fixes a compiler
failure on older kernel [0] and now I'm seeing this while trying to
build v5.1:

ld: arch/x86/boot/compressed/pgtable_64.o:(.bss+0x0): multiple definition of `__force_order';
arch/x86/boot/compressed/kaslr_64.o:(.bss+0x0): first defined here
ld: warning: arch/x86/boot/compressed/efi_thunk_64.o: missing .note.GNU-stack section implies executable stack
ld: NOTE: This behaviour is deprecated and will be removed in a future version of the linker
ld: arch/x86/boot/compressed/head_64.o: warning: relocation in read-only section `.head.text'
ld: warning: arch/x86/boot/compressed/vmlinux has a LOAD segment with RWX permissions
ld: warning: creating DT_TEXTREL in a PIE
make[2]: *** [arch/x86/boot/compressed/Makefile:118: arch/x86/boot/compressed/vmlinux] Error 1
make[1]: *** [arch/x86/boot/Makefile:112: arch/x86/boot/compressed/vmlinux] Error 2
make: *** [arch/x86/Makefile:283: bzImage] Error 2

[0] http://lore.kernel.org/lkml/20220213182443.4037039-1-keescook@chromium.org (local)

But we should try to bisect to see what cauased the above kmod test 0006
to start failing.

BTW if someone beats me to bisecting the above it would be appreciated.
I have a feeling having old gcc / linker, etc would be easier.

  Luis